6W3O

Crystal structure of ligand-binding domain of Campylobacter jejuni chemoreceptor Tlp3 in complex with 4-methylisoleucine


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.42 Å
  • R-Value Free: 0.162 
  • R-Value Work: 0.115 
  • R-Value Observed: 0.117 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structure-Activity Relationship Study Reveals the Molecular Basis for Specific Sensing of Hydrophobic Amino Acids by theCampylobacter jejuniChemoreceptor Tlp3.

Khan, M.F.Machuca, M.A.Rahman, M.M.Koc, C.Norton, R.S.Smith, B.J.Roujeinikova, A.

(2020) Biomolecules 10

  • DOI: 10.3390/biom10050744
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Chemotaxis is an important virulence factor of the foodborne pathogen Campylobacter jejuni . Inactivation of chemoreceptor Tlp3 reduces the ability of C. jejuni to invade human and chicken cells and to colonise the jejunal mucosa of ...

    Chemotaxis is an important virulence factor of the foodborne pathogen Campylobacter jejuni . Inactivation of chemoreceptor Tlp3 reduces the ability of C. jejuni to invade human and chicken cells and to colonise the jejunal mucosa of mice. Knowledge of the structure of the ligand-binding domain (LBD) of Tlp3 in complex with its ligands is essential for a full understanding of the molecular recognition underpinning chemotaxis. To date, the only structure in complex with a signal molecule is Tlp3 LBD bound to isoleucine. Here, we used in vitro and in silico screening to identify eight additional small molecules that signal through Tlp3 as attractants by directly binding to its LBD, and determined the crystal structures of their complexes. All new ligands (leucine, valine, α-amino-N-valeric acid, 4-methylisoleucine, β-methylnorleucine, 3-methylisoleucine, alanine, and phenylalanine) are nonpolar amino acids chemically and structurally similar to isoleucine. X-ray crystallographic analysis revealed the hydrophobic side-chain binding pocket and conserved protein residues that interact with the ammonium and carboxylate groups of the ligands determine the specificity of this chemoreceptor. The uptake of hydrophobic amino acids plays an important role in intestinal colonisation by C. jejuni , and our study suggests that C. jejuni seeks out hydrophobic amino acids using chemotaxis.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Methyl-accepting chemotaxis protein
A, B
254Campylobacter jejuniMutation(s): 0 
Gene Names: D8X59_02240
Find proteins for A0A3X8N4T9 (Campylobacter jejuni)
Go to UniProtKB:  A0A3X8N4T9
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SKG
Query on SKG

Download CCD File 
A, B
4-methylisoleucine
C7 H15 N O2
VFEDCKXLINRKLV-WDSKDSINSA-N
 Ligand Interaction
SO4
Query on SO4

Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
CL
Query on CL

Download CCD File 
B
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
NA
Query on NA

Download CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.42 Å
  • R-Value Free: 0.162 
  • R-Value Work: 0.115 
  • R-Value Observed: 0.117 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.42α = 90
b = 137.72β = 94.04
c = 48.79γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
SCALAdata scaling
PDB_EXTRACTdata extraction
iMOSFLMdata reduction
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Australian Research Council (ARC)Australia--

Revision History 

  • Version 1.0: 2020-05-20
    Type: Initial release
  • Version 1.1: 2020-05-27
    Changes: Database references